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1.
J Nutr ; 150(9): 2336-2345, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32692358

RESUMO

BACKGROUND: α-Lipoic acid (LA) is a dietary supplement for maintaining energy balance, but well-controlled clinical trials in otherwise healthy, overweight adults using LA supplementation are lacking. OBJECTIVES: The primary objective was to evaluate whether LA supplementation decreases elevated plasma triglycerides in overweight or obese adults. Secondary aims examined if LA promotes weight loss and improves oxidative stress and inflammation. METHODS: Overweight adults [n = 81; 57% women; 21-60 y old; BMI (in kg/m2) ≥ 25] with elevated plasma triglycerides ≥100 mg/dL were enrolled in a 24-wk, randomized, double-blind, controlled trial, assigned to either (R)-α-lipoic acid (R-LA; 600 mg/d) or matching placebo, and advised not to change their diet or physical activity. Linear models were used to evaluate treatment effects from baseline for primary and secondary endpoints. RESULTS: R-LA did not decrease triglyceride concentrations, but individuals on R-LA had a greater reduction in BMI at 24 wk than the placebo group (-0.8; P = 0.04). The effect of R-LA on BMI was correlated to changes in plasma triglycerides (r = +0.50, P = 0.004). Improvement in body weight was greater at 24 wk in R-LA subgroups than in placebo subgroups. Women and obese participants (BMI ≥ 35) showed greater weight loss (-5.0% and -4.8%, respectively; both P < 0.001) and loss of body fat (-9.4% and -8.6%, respectively; both P < 0.005). Antioxidant gene expression in mononuclear cells at 24 wk was greater in the R-LA group (Heme oxygenase 1 [HMOX1] : +22%; P = 0.02) than in placebo. Less urinary F2-isoprostanes (-25%; P = 0.005), blood leukocytes (-10.1%; P = 0.01), blood thrombocytes (-5.1%; P = 0.03), and ICAM-1 (-7.4%; P = 0.04) at 24 wk were also observed in the R-LA group than in placebo. CONCLUSIONS: Long-term LA supplementation results in BMI loss, greater antioxidant enzyme synthesis, and less potential for inflammation in overweight adults. Improved cellular bioenergetics is also evident in some individuals given R-LA.This trial was registered at clinicaltrials.gov as NCT00765310.


Assuntos
Suplementos Nutricionais , Sobrepeso/tratamento farmacológico , Ácido Tióctico/administração & dosagem , Triglicerídeos/sangue , Adulto , Esquema de Medicação , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Redução de Peso , Adulto Jovem
2.
J Nutr ; 148(12): 1924-1930, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30517727

RESUMO

Background: Inadequate vitamin E and magnesium intakes are of concern for older adults owing to the associated incidence of age-related diseases. Objective: This study was designed to determine the extent to which a 16-wk intervention with hazelnuts alters vitamin E and magnesium status in a group of older men and women, and used a pre-post intervention design without a control group to adjust for temporal changes. Methods: Participants (n = 32 including 22 women; mean ± SD age: 63 ± 6 y) consumed hazelnuts (∼57 g/d) for 16 wk. Blood and urine samples and anthropomorphic measures were taken at the start and end of the intervention to determine plasma concentrations of α-tocopherol and serum concentrations of magnesium, lipids, glucose, insulin, and high-sensitivity C-reactive protein along with urinary vitamin E metabolites; several other micronutrients were measured by a lymphocyte proliferation assay. There were 3 primary endpoints, calculated as the mean changes in measurements between baseline and the end of the 16-wk intervention for 1) plasma α-tocopherol, 2) urinary α-carboxyethyl hydroxychromanol (α-CEHC; an α-tocopherol metabolite), and 3) serum magnesium. Results: Hazelnut consumption increased concentrations of the urinary α-tocopherol metabolite α-CEHC (mean ± SD: 0.84 ± 0.45 to 1.14 ± 0.50 µmol/g creatinine; P = 0.0006). In addition, hazelnut consumption increased serum concentrations of magnesium (+2.1%, P = 0.05), decreased concentrations of fasting glucose (-3.4%, P = 0.03) and LDL cholesterol (-6.0%, P = 0.02), and decreased total:HDL cholesterol ratios (-4.5%, P = 0.009). No significant changes were observed in blood pressure, lymphocyte proliferation assays, and serum concentrations of insulin, high-sensitivity C-reactive protein, triglyceride, α-tocopherol, or HDL cholesterol. Conclusions: Consuming hazelnuts improves a biomarker of vitamin E status in older adults. Vitamin E is a shortfall micronutrient, as identified by the Dietary Guidelines for Americans 2015-2020, which frequently is consumed at levels less than the Estimated Average Requirement of 12 mg/d; thus, hazelnuts should be considered as part of a healthy dietary pattern. This trial was registered at clinicaltrials.gov as NCT03485989.


Assuntos
Corylus , alfa-Tocoferol/sangue , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , Feminino , Humanos , Lipídeos/sangue , Ativação Linfocitária , Magnésio/sangue , Masculino , Pessoa de Meia-Idade , alfa-Tocoferol/urina
3.
Crit Rev Food Sci Nutr ; 55(14): 1968-91, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24941429

RESUMO

We reviewed recent scientific evidence regarding the effects of multivitamin/mineral (MVM) supplements on risk of chronic diseases, including cancer, cardiovascular disease, and age-related eye diseases. Data from randomized controlled trials (RCTs) and observational, prospective cohort studies were examined. The majority of scientific studies investigating the use of MVM supplements in chronic disease risk reduction reported no significant effect. However, the largest and longest RCT of MVM supplements conducted to date, the Physicians' Health Study II (PHS II), found a modest and significant reduction in total and epithelial cancer incidence in male physicians, consistent with the Supplémentation en Vitamines et Minéraux Antioxydants (SU.VI.MAX) trial. In addition, PHS II found a modest and significant reduction in the incidence of nuclear cataract, in agreement with several other RCTs and observational, prospective cohort studies. The effects of MVM use on other subtypes of cataract and age-related macular degeneration remain unclear. Neither RCTs nor prospective cohort studies are without their limitations. The placebo-controlled trial design of RCTs may be inadequate for nutrient interventions, and residual confounding, measurement error, and the possibility of reverse causality are inherent to any observational study. National surveys show that micronutrient inadequacies are widespread in the US and that dietary supplements, of which MVMs are the most common type, help fulfill micronutrient requirements in adults and children.


Assuntos
Suplementos Nutricionais/estatística & dados numéricos , Estudos Observacionais como Assunto/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Oligoelementos/uso terapêutico , Vitaminas/uso terapêutico , Envelhecimento , Doenças Cardiovasculares/prevenção & controle , Doença Crônica , Oftalmopatias/prevenção & controle , Feminino , Humanos , Masculino , Neoplasias/prevenção & controle , Estudos Prospectivos , Oligoelementos/administração & dosagem , Resultado do Tratamento , Vitaminas/administração & dosagem
4.
Mediators Inflamm ; 2015: 274314, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25960613

RESUMO

In this study we investigated the role of astragaloside IV (AS-IV), one of the major active constituents purified from the Chinese medicinal herb Astragalus membranaceus, in LPS-induced acute inflammatory responses in mice in vivo and examined possible underlying mechanisms. Mice were assigned to four groups: vehicle-treated control animals; AS-IV-treated animals (10 mg/kg b.w. AS-IV daily i.p. injection for 6 days); LPS-treated animals; and AS-IV plus LPS-treated animals. We found that AS-IV treatment significantly inhibited LPS-induced increases in serum levels of MCP-1 and TNF by 82% and 49%, respectively. AS-IV also inhibited LPS-induced upregulation of inflammatory gene expression in different organs. Lung mRNA levels of cellular adhesion molecules, MCP-1, TNFα, IL-6, and TLR4 were significantly attenuated, and lung neutrophil infiltration and activation were strongly inhibited, as reflected by decreased myeloperoxidase content, when the mice were pretreated with AS-IV. Similar results were observed in heart, aorta, kidney, and liver. Furthermore, AS-IV significantly suppressed LPS-induced NF-κB and AP-1 DNA-binding activities in lung and heart. In conclusion, our data provide new in vivo evidence that AS-IV effectively inhibits LPS-induced acute inflammatory responses by modulating NF-κB and AP-1 signaling pathways. Our results suggest that AS-IV may be useful for the prevention or treatment of inflammatory diseases.


Assuntos
Astragalus propinquus/química , Inflamação/metabolismo , NF-kappa B/metabolismo , Saponinas/química , Fator de Transcrição AP-1/metabolismo , Triterpenos/química , Animais , Quimiocina CCL2/sangue , Quimiocina CCL2/metabolismo , Feminino , Inflamação/sangue , Interleucina-6/metabolismo , Lipopolissacarídeos/química , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Peroxidase/metabolismo , Transdução de Sinais , Distribuição Tecidual , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo
5.
Annu Rev Nutr ; 33: 45-70, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23642198

RESUMO

New evidence for the regulation of vitamin C homeostasis has emerged from several studies of human genetic variation. Polymorphisms in the genes encoding sodium-dependent vitamin C transport proteins are strongly associated with plasma ascorbate levels and likely impact tissue cellular vitamin C status. Furthermore, genetic variants of proteins that suppress oxidative stress or detoxify oxidatively damaged biomolecules, i.e., haptoglobin, glutathione-S-transferases, and possibly manganese superoxide dismutase, affect ascorbate levels in the human body. There also is limited evidence for a role of glucose transport proteins. In this review, we examine the extent of the variation in these genes, their impact on vitamin C status, and their potential role in altering chronic disease risk. We conclude that future epidemiological studies should take into account genetic variation in order to successfully determine the role of vitamin C nutriture or supplementation in human vitamin C status and chronic disease risk.


Assuntos
Ácido Ascórbico/metabolismo , Variação Genética , Homeostase , Oxirredutases/metabolismo , Transportadores de Sódio Acoplados à Vitamina C/genética , Animais , Transporte Biológico , Humanos , Transportadores de Sódio Acoplados à Vitamina C/metabolismo
6.
JAMA ; 311(20): 2074-82, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24838476

RESUMO

IMPORTANCE: Maternal smoking during pregnancy adversely affects offspring lung development, with lifelong decreases in pulmonary function and increased asthma risk. In a primate model, vitamin C blocked some of the in-utero effects of nicotine on lung development and offspring pulmonary function. OBJECTIVE: To determine if newborns of pregnant smokers randomized to receive daily vitamin C would have improved results of pulmonary function tests (PFTs) and decreased wheezing compared with those randomized to placebo. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind trial conducted in 3 sites in the Pacific Northwest between March 2007 and January 2011. One hundred fifty-nine newborns of randomized pregnant smokers (76 vitamin C treated and 83 placebo treated) and 76 newborns of pregnant nonsmokers were studied with newborn PFTs. Follow-up assessment including wheezing was assessed through age 1 year, and PFTs were performed at age 1 year. INTERVENTIONS: Pregnant women were randomized to receive vitamin C (500 mg/d) (n = 89) or placebo (n = 90). MAIN OUTCOMES AND MEASURES: The primary outcome was measurement of newborn pulmonary function (ratio of the time to peak tidal expiratory flow to expiratory time [TPTEF:TE] and passive respiratory compliance per kilogram [Crs/kg]) within 72 hours of age. Secondary outcomes included incidence of wheezing through age 1 year and PFT results at age 1 year. A subgroup of pregnant smokers and nonsmokers had genotyping performed. RESULTS: Newborns of women randomized to vitamin C (n = 76), compared with those randomized to placebo (n = 83), had improved pulmonary function as measured by TPTEF:TE (0.383 vs 0.345 [adjusted 95% CI for difference, 0.011-0.062]; P = .006) and Crs/kg (1.32 vs 1.20 mL/cm H2O/kg [95% CI, 0.02-0.20]; P = .01). Offspring of women randomized to vitamin C had significantly decreased wheezing through age 1 year (15/70 [21%] vs 31/77 [40%]; relative risk, 0.56 [95% CI, 0.33-0.95]; P = .03). There were no significant differences in the 1-year PFT results between the vitamin C and placebo groups. The effect of maternal smoking on newborn lung function was associated with maternal genotype for the α5 nicotinic receptor (rs16969968) (P < .001 for interaction). CONCLUSIONS AND RELEVANCE: Supplemental vitamin C taken by pregnant smokers improved newborn PFT results and decreased wheezing through 1 year in the offspring. Vitamin C in pregnant smokers may be an inexpensive and simple approach to decrease the effects of smoking in pregnancy on newborn pulmonary function and respiratory morbidities. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00632476.


Assuntos
Ácido Ascórbico/uso terapêutico , Pulmão/fisiopatologia , Sons Respiratórios , Fumar/efeitos adversos , Vitaminas/uso terapêutico , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Lactente , Recém-Nascido , Doenças do Recém-Nascido/prevenção & controle , Gravidez , Cuidado Pré-Natal , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Testes de Função Respiratória , Sons Respiratórios/etiologia , Sons Respiratórios/fisiopatologia , Doenças Respiratórias/prevenção & controle , Adulto Jovem
7.
Nutrients ; 15(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37375594

RESUMO

Despite the reported prevalence of micronutrient deficiencies in older adults, it is not yet established whether multivitamin/multimineral (MV/MM) supplements improve blood micronutrient status in individuals over the age of 65. Therefore, a cohort of 35 healthy men (>67 years) was recruited for an MV/MM supplementation trial. The primary endpoint was, as an indicator of micronutrient status, changes in blood micronutrient biomarkers from baseline to at least six months of supplementation with MV/MM or placebo. The secondary endpoint was basal O2 consumption in monocytes as an indicator of cellular metabolism. MV/MM supplementation improved blood concentrations of pyridoxal phosphate, calcifediol, α-tocopherol, and ß-carotene concentrations throughout the cohort. By contrast, those in the placebo group generally showed declines in blood vitamin concentrations and an increased prevalence of suboptimal vitamin status during the study period. On the other hand, MV/MM supplementation did not significantly affect blood mineral concentrations, i.e., calcium, copper, iron, magnesium, and zinc. Interestingly, MV/MM supplementation prevented the decline in monocyte O2 consumption rate. Overall, MV/MM use improves or prevents declines in vitamin, but not mineral, status and limits declines in cellular O2 consumption, which may have important implications for metabolism and immune health in healthy older men.


Assuntos
Oligoelementos , Vitaminas , Masculino , Humanos , Idoso , Suplementos Nutricionais , Minerais , Micronutrientes , Biomarcadores , Metabolismo Energético , Método Duplo-Cego
8.
Am J Physiol Regul Integr Comp Physiol ; 302(5): R587-97, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22049228

RESUMO

To determine the effects of age and lipoic acid supplementation on hepatic gene expression, we fed young (3 mo) and old (24 mo) male Fischer 344 rats a diet with or without 0.2% (wt/wt) R-α-lipoic acid (LA) for 2 wk. Total RNA isolated from liver tissue was analyzed by Affymetrix microarray to examine changes in transcriptional profiles. Results showed elevated proinflammatory gene expression in the aging liver and evidence for increased immune cell activation and tissue remodeling, together representing 45% of the age-related transcriptome changes. In addition, age-related increases in transcripts of genes related to fatty acid, triglyceride, and cholesterol synthesis, including acetyl-CoA carboxylase-ß (Acacb) and fatty acid synthase (Fasn), were observed. Supplementation of old animals with LA did not reverse the necroinflammatory phenotype but, intriguingly, altered the expression of genes governing circadian rhythm. Most notably, Arntl, Npas2, and Per changed in a coordinated manner with respect to rhythmic transcription. LA further caused a decrease in transcripts of several bile acid and lipid synthesis genes, including Acacb and Fasn, which are regulated by first-order clock transcription factors. Similar effects of LA supplementation on bile acid and lipid synthesis genes were observed in young animals. Transcript changes of lipid metabolism genes were corroborated by a decrease in FASN and ACC protein levels. We conclude that advanced age is associated with a necroinflammatory phenotype and increased lipid synthesis, while chronic LA supplementation influences hepatic genes associated with lipid and energy metabolism and circadian rhythm, regardless of age.


Assuntos
Envelhecimento/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Perfilação da Expressão Gênica , Hepatite/prevenção & controle , Metabolismo dos Lipídeos/efeitos dos fármacos , Ácido Tióctico/farmacologia , Ácido Tióctico/uso terapêutico , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Envelhecimento/metabolismo , Animais , Ritmo Circadiano/genética , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/genética , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/metabolismo , Suplementos Nutricionais , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Hepatite/genética , Hepatite/metabolismo , Metabolismo dos Lipídeos/fisiologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Modelos Animais , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Ratos , Ratos Endogâmicos F344 , Ácido Tióctico/administração & dosagem
9.
Crit Rev Food Sci Nutr ; 52(9): 815-29, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22698272

RESUMO

The recommended dietary allowance (RDA) of vitamin C has traditionally been based on the prevention of the vitamin C deficiency disease, scurvy. While higher intakes of vitamin C may exert additional health benefits, the limited Phase III randomized placebo-controlled trials (RCTs) of vitamin C supplementation have not found consistent benefit with respect to chronic disease prevention. To date, this has precluded upward adjustments of the current RDA. Here we argue that Phase III RCTs-designed principally to test the safety and efficacy of pharmaceutical drugs-are ill suited to assess the health benefits of essential nutrients; and the currently available scientific evidence is sufficient to determine the optimum intake of vitamin C in humans. This evidence establishes biological plausibility and mechanisms of action for vitamin C in the primary prevention of coronary heart disease, stroke, and cancer; and is buttressed by consistent data from prospective cohort studies based on blood analysis or dietary intake and well-designed Phase II RCTs. These RCTs show that vitamin C supplementation lowers hypertension, endothelial dysfunction, chronic inflammation, and Helicobacter pylori infection, which are independent risk factors of cardiovascular diseases and certain cancers. Furthermore, vitamin C acts as a biological antioxidant that can lower elevated levels of oxidative stress, which also may contribute to chronic disease prevention. Based on the combined evidence from human metabolic, pharmacokinetic, and observational studies and Phase II RCTs, we conclude that 200 mg per day is the optimum dietary intake of vitamin C for the majority of the adult population to maximize the vitamin's potential health benefits with the least risk of inadequacy or adverse health effects.


Assuntos
Ácido Ascórbico/administração & dosagem , Promoção da Saúde , Necessidades Nutricionais , Adulto , Animais , Antioxidantes/administração & dosagem , Antioxidantes/uso terapêutico , Ácido Ascórbico/efeitos adversos , Ácido Ascórbico/sangue , Ácido Ascórbico/uso terapêutico , Deficiência de Ácido Ascórbico/prevenção & controle , Doenças Cardiovasculares/prevenção & controle , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Suplementos Nutricionais/efeitos adversos , Humanos , Política Nutricional , Estresse Oxidativo , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Cancers (Basel) ; 14(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35740528

RESUMO

Cancer cells often display impaired mitochondrial function, reduced oxidative phosphorylation, and augmented aerobic glycolysis (Warburg effect) to fulfill their bioenergetic and biosynthetic needs. Caveolin-1 (CAV1) is a scaffolding protein that promotes cancer cell migration, invasion, and metastasis in a manner dependent on CAV1 phosphorylation on tyrosine-14 (pY14). Here, we show that CAV1 expression increased glycolysis rates, while mitochondrial respiration was reduced by inhibition of the mitochondrial complex IV. These effects correlated with increased reactive oxygen species (ROS) levels that favored CAV1-induced migration and invasion. Interestingly, pY14-CAV1 promoted the metabolic switch associated with increased migration/invasion and augmented ROS-inhibited PTP1B, a phosphatase that controls pY14 levels. Finally, the glycolysis inhibitor 2-deoxy-D-glucose reduced CAV1-enhanced migration in vitro and metastasis in vivo of murine melanoma cells. In conclusion, CAV1 promotes the Warburg effect and ROS production, which inhibits PTP1B to augment CAV1 phosphorylation on tyrosine-14, thereby increasing the metastatic potential of cancer cells.

11.
Am J Physiol Heart Circ Physiol ; 301(3): H712-20, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21724870

RESUMO

Redox-active transition metal ions, such as iron and copper, may play an important role in vascular inflammation, which is an etiologic factor in atherosclerotic vascular diseases. In this study, we investigated whether tetrathiomolybdate (TTM), a highly specific copper chelator, can act as an anti-inflammatory agent, preventing lipopolysaccharide (LPS)-induced inflammatory responses in vivo. Female C57BL/6N mice were daily gavaged with TTM (30 mg/kg body wt) or vehicle control. After 3 wk, animals were injected intraperitoneally with 50 µg LPS or saline buffer and killed 3 h later. Treatment with TTM reduced serum ceruloplasmin activity by 43%, a surrogate marker of bioavailable copper, in the absence of detectable hepatotoxicity. The concentrations of both copper and molybdenum increased in various tissues, whereas the copper-to-molybdenum ratio decreased, consistent with reduced copper bioavailability. TTM treatment did not have a significant effect on superoxide dismutase activity in heart and liver. Furthermore, TTM significantly inhibited LPS-induced inflammatory gene transcription in aorta and heart, including vascular and intercellular adhesion molecule-1 (VCAM-1 and ICAM-1, respectively), monocyte chemotactic protein-1 (MCP-1), interleukin-6, and tumor necrosis factor (TNF)-α (ANOVA, P < 0.05); consistently, protein levels of VCAM-1, ICAM-1, and MCP-1 in heart were also significantly lower in TTM-treated animals. Similar inhibitory effects of TTM were observed on activation of nuclear factor-κB (NF-κB) and activator protein-1 (AP-1) in heart and lungs. Finally, TTM significantly inhibited LPS-induced increases of serum levels of soluble ICAM-1, MCP-1, and TNF-α (ANOVA, P < 0.05). These data indicate that copper chelation with TTM inhibits LPS-induced inflammatory responses in aorta and other tissues of mice, most likely by inhibiting activation of the redox-sensitive transcription factors, NF-κB and AP-1. Therefore, copper appears to play an important role in vascular inflammation, and TTM may have value as an anti-inflammatory or anti-atherogenic agent.


Assuntos
Anti-Inflamatórios/farmacologia , Quelantes/farmacologia , Cobre/metabolismo , Inflamação/prevenção & controle , Lipopolissacarídeos , Molibdênio/farmacologia , Análise de Variância , Animais , Ceruloplasmina/metabolismo , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Oxirredução , RNA Mensageiro/metabolismo , Superóxido Dismutase/metabolismo , Fator de Transcrição AP-1/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
12.
Chem Res Toxicol ; 24(1): 30-4, 2011 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21047085

RESUMO

Ergothioneine (2-mercaptohistidine trimethylbetaine) is a naturally occurring amino acid analogue found in up to millimolar concentrations in several tissues and biological fluids. However, the biological functions of ergothioneine remain incompletely understood. In this study, we investigated the role of ergothioneine in copper-induced oxidative damage to DNA and protein, using two copper-containing systems: Cu(II) with ascorbate and Cu(II) with H(2)O(2) [0.1 mM Cu(II), 1 mM ascorbate, and 1 mM H(2)O(2)]. Oxidative damage to DNA and bovine serum albumin was measured as strand breakage and protein carbonyl formation, respectively. Ergothioneine (0.1-1.0 mM) provided strong, dose-dependent protection against oxidation of DNA and protein in both copper-containing systems. In contrast, only limited protection was observed with the purported hydroxyl radical scavengers, dimethyl sulfoxide and mannitol, even at concentrations as high as 100 mM. Ergothioneine also significantly inhibited copper-catalyzed oxidation of ascorbate and competed effectively with histidine and 1,10-phenanthroline for binding of cuprous copper, but not cupric copper, as demonstrated by UV-visible and low-temperature electron spin resonance techniques. We conclude that ergothioneine is a potent, natural sulfur-containing antioxidant that prevents copper-dependent oxidative damage to biological macromolecules by forming a redox-inactive ergothioneine-copper complex.


Assuntos
Complexos de Coordenação/química , Cobre/toxicidade , Dano ao DNA , Ergotioneína/química , Animais , Ácido Ascórbico/química , Bovinos , Complexos de Coordenação/toxicidade , Cobre/química , DNA/metabolismo , Dimetil Sulfóxido/química , Espectroscopia de Ressonância de Spin Eletrônica , Ergotioneína/farmacologia , Sequestradores de Radicais Livres/química , Histidina/química , Peróxido de Hidrogênio/química , Manitol/química , Oxirredução , Fenantrolinas/química , Carbonilação Proteica , Soroalbumina Bovina/química
13.
Alzheimer Dis Assoc Disord ; 25(1): 49-57, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20856100

RESUMO

INTRODUCTION: There is great interest in the nutritional strategies for the prevention of age-related cognitive decline, yet the best methods for nutritional assessment in the populations at risk for dementia are still evolving. Our study objective was to examine the reliability and validity of the 2 common nutritional assessments (plasma nutrient biomarkers and Food Frequency Questionnaire) in the people at risk for dementia. METHODS: Thirty-eight elders, half with amnestic-mild cognitive impairment were recruited. Nutritional assessments were collected together at the baseline and again at 1 month. Intraclass and Pearson correlation coefficients quantified reliability and validity. RESULTS: Twenty-six nutrients were examined. The reliability was very good or better for 77% (20/26, intraclass correlation coefficients or ICC ≥0.75) of the plasma nutrient biomarkers and for 88% of the food frequency questionnaires (FFQ) estimates. Twelve of the nutrient biomarkers were as reliable as the commonly measured plasma cholesterol (ICC≥0.92). FFQ and plasma long-chain fatty acids (docosahexaenoic acid, r=0.39, eicosapentaenoic acid, r=0.39) and carotenoids (α-carotene, r=0.49; lutein + zeaxanthin, r=0.48; ß-carotene, r=0.43; ß-cryptoxanthin, r=0.41) were correlated, but these significant correlations were present only in non-impaired elders. CONCLUSION: The reliability and validity of the FFQ and nutrient biomarkers vary according to the nutrient of interest. Memory deficit attenuates validity and inflates reliability of FFQ reports. Many plasma nutrient biomarkers have very good reliability over 1-month, regardless of memory state. This objective method can circumvent sources of error seen in other less direct and subjective methods of nutritional assessment.


Assuntos
Biomarcadores/sangue , Dieta , Avaliação Nutricional , Estado Nutricional , Inquéritos e Questionários , Idoso , Transtornos Cognitivos , Feminino , Alimentos , Humanos , Masculino , Projetos Piloto , Reprodutibilidade dos Testes
14.
Arterioscler Thromb Vasc Biol ; 29(5): 732-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19251588

RESUMO

OBJECTIVE: Vascular oxidative stress and inflammation are contributing factors in atherosclerosis. We recently found that the iron chelator, desferrioxamine (DFO), suppresses NADPH oxidase-mediated oxidative stress and expression of cellular adhesion molecules in mice treated with lipopolysaccharide (LPS). The objective of the present study was to investigate whether and how LPS and iron enhance, and DFO inhibits, NADPH oxidase activity in human aortic endothelial cells (HAECs). METHODS AND RESULTS: Incubation of HAECs for 24 hours with 5 microg/mL LPS led to a 4-fold increase in NADPH oxidase activity, which was strongly suppressed by pretreatment of the cells for 24 hours with 100 micromol/L DFO. Incubating HAECs with LPS also significantly increased cellular iron and heme levels and mRNA and protein levels of p22phox, a heme-containing, catalytic subunit of NADPH oxidase. All of these effects of LPS on HAECs were strongly inhibited by DFO. Exposing HAECs to 100 micromol/L iron (ferric citrate) for 48 hours exerted similar effects as LPS, and these effects were strongly inhibited by coincubation with DFO. Furthermore, neither LPS nor DFO affected mRNA and protein levels of p47phox a nonheme-containing, regulatory subunit of NADPH oxidase, or the mRNA level of NOX4, an isoform of the principal catalytic subunit of NADPH oxidase in endothelial cells. In contrast, heme oxygenase-1 was strongly suppressed by DFO, both in the absence and presence of LPS or iron. CONCLUSIONS: Our data indicate that prolonged exposure to LPS or iron increases endothelial NADPH oxidase activity by increasing p22phox gene transcription and cellular levels of iron, heme, and p22phox protein. Iron chelation by DFO effectively suppresses endothelial NADPH oxidase activity, which may be helpful as an adjunct in reducing vascular oxidative stress and inflammation in atherosclerosis.


Assuntos
Células Endoteliais/metabolismo , Heme/metabolismo , Ferro/metabolismo , NADPH Oxidases/metabolismo , Aorta/citologia , Aorta/metabolismo , Aterosclerose/fisiopatologia , Células Cultivadas , Desferroxamina/farmacologia , Células Endoteliais/enzimologia , Humanos , Lipopolissacarídeos , NADPH Oxidases/efeitos dos fármacos , Estresse Oxidativo/fisiologia
16.
Oncogene ; 39(18): 3693-3709, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32152405

RESUMO

Caveolin-1 (CAV1) enhanced migration, invasion, and metastasis of cancer cells is inhibited by co-expression of the glycoprotein E-cadherin. Although the two proteins form a multiprotein complex that includes ß-catenin, it remained unclear how this would contribute to blocking the metastasis promoting function of CAV1. Here, we characterized by mass spectrometry the protein composition of CAV1 immunoprecipitates from B16F10 murine melanoma cells expressing or not E-cadherin. The novel protein tyrosine phosphatase PTPN14 was identified by mass spectrometry analysis exclusively in co-immunoprecipitates of CAV1 with E-cadherin. Interestingly, PTPN14 is implicated in controlling metastasis, but only few known PTPN14 substrates exist. We corroborated by western blotting experiments that PTPN14 and CAV1 co-inmunoprecipitated in the presence of E-cadherin in B16F10 melanoma and other cancer cells. Moreover, the CAV1(Y14F) mutant protein was shown to co-immunoprecipitate with PTPN14 even in the absence of E-cadherin, and overexpression of PTPN14 reduced CAV1 phosphorylation on tyrosine-14, as well as suppressed CAV1-enhanced cell migration, invasion and Rac-1 activation in B16F10, metastatic colon [HT29(US)] and breast cancer (MDA-MB-231) cell lines. Finally, PTPN14 overexpression in B16F10 cells reduced the ability of CAV1 to induce metastasis in vivo. In summary, we identify here CAV1 as a novel substrate for PTPN14 and show that overexpression of this phosphatase suffices to reduce CAV1-induced metastasis.


Assuntos
Caderinas/genética , Caveolina 1/genética , Melanoma Experimental/genética , Proteínas Tirosina Fosfatases não Receptoras/genética , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Melanoma Experimental/patologia , Camundongos , Invasividade Neoplásica , Metástase Neoplásica , Fosforilação/genética , beta Catenina/genética
17.
Circulation ; 117(3): 421-8, 2008 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-18158360

RESUMO

BACKGROUND: Vascular inflammation and lipid deposition are prominent features of atherosclerotic lesion formation. We have shown previously that the dithiol compound alpha-lipoic acid (LA) exerts antiinflammatory effects by inhibiting tumor necrosis factor-alpha- and lipopolysaccharide-induced endothelial and monocyte activation in vitro and lipopolysaccharide-induced acute inflammatory responses in vivo. Here, we investigated whether LA inhibits atherosclerosis in apolipoprotein E-deficient (apoE-/-) and apoE/low-density lipoprotein receptor-deficient mice, 2 well-established animal models of human atherosclerosis. METHODS AND RESULTS: Four-week-old female apoE-/- mice (n=20 per group) or apoE/low-density lipoprotein receptor-deficient mice (n=21 per group) were fed for 10 weeks a Western-type chow diet containing 15% fat and 0.125% cholesterol without or with 0.2% (wt/wt) R,S-LA or a normal chow diet containing 4% fat without or with 0.2% (wt/wt) R-LA, respectively. Supplementation with LA significantly reduced atherosclerotic lesion formation in the aortic sinus of both mouse models by approximately 20% and in the aortic arch and thoracic aorta of apoE-/- and apoE/low-density lipoprotein receptor-deficient mice by approximately 55% and 40%, respectively. This strong antiatherogenic effect of LA was associated with almost 40% less body weight gain and lower serum and very low-density lipoprotein levels of triglycerides but not cholesterol. In addition, LA supplementation reduced aortic expression of adhesion molecules and proinflammatory cytokines and aortic macrophage accumulation. These antiinflammatory effects of LA were more pronounced in the aortic arch and the thoracic aorta than in the aortic sinus, reflecting the corresponding reductions in atherosclerosis. CONCLUSIONS: Our study shows that dietary LA supplementation inhibits atherosclerotic lesion formation in 2 mouse models of human atherosclerosis, an inhibition that appears to be due to the "antiobesity," antihypertriglyceridemic, and antiinflammatory effects of LA. LA may be a useful adjunct in the prevention and treatment of atherosclerotic vascular diseases.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/tratamento farmacológico , Receptores de LDL/deficiência , Ácido Tióctico/farmacologia , Animais , Aterosclerose/prevenção & controle , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle , Camundongos , Ácido Tióctico/administração & dosagem , Triglicerídeos/sangue
18.
J Alzheimers Dis ; 16(1): 93-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19158425

RESUMO

The brain maintains high levels of ascorbic acid (AA) despite a concentration gradient favoring diffusion from brain to peripheral tissues. Dietary antioxidants, including AA, appear to modify the risk of Alzheimer's disease (AD). The objective of this study was to test the hypothesis that neurodegeneration in AD is modified by brain levels of AA. Thirty-two patients with mild to moderate AD participated in a biomarker study involving standardized clinical assessments over one year. Cerebrospinal fluid (CSF) and serum were collected at baseline for AA and albumin content. Cognitive measures were collected at baseline and one year. CSF and plasma AA failed to predict cognitive decline independently, however, CSF: plasma AA ratio did. After adding CSF Albumin Index (an established marker of blood-brain barrier integrity) to the regression models the effect of CSF: plasma AA ratio as a predictor of cognitive decline was weakened. CSF: plasma AA ratio predicts rate of decline in AD. This relationship may indicate that the CSF: plasma AA ratio is an index of AA availability to the brain or may be an artifact of a relationship between blood-brain barrier impairment and neurodegeneration.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/psicologia , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Química Encefálica/fisiologia , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/psicologia , Idoso , Ácido Ascórbico/sangue , Ácido Ascórbico/líquido cefalorraquidiano , Barreira Hematoencefálica/metabolismo , Interpretação Estatística de Dados , Progressão da Doença , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estudos Prospectivos
19.
J Nutr Gerontol Geriatr ; 38(4): 307-328, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31502930

RESUMO

Micronutrient inadequacies are common in older adults and using a multivitamin/multimineral supplement (MVM) may improve their nutritional status. National Health and Nutrition Examination Survey data were analyzed to determine micronutrient intakes based on diet and MVM use in adults aged ≥51 years. Deficiencies were evaluated using nutrient biomarkers. The National Cancer Institute Method was used to estimate usual intakes of 18 micronutrients stratified by age and frequency of MVM use. Compared with food alone, MVM use was associated with higher nutrient intake and lower prevalence of inadequacies of almost all micronutrients examined and improved nutrient biomarker status of folate, iodine, selenium, and vitamins B6, B12, and D. Regular MVM use (≥16 days/month) decreased the odds of clinical deficiency (defined by biomarker status) of vitamins B6 and D but increased the proportion exceeding the tolerable upper intake level of folic acid. Vitamin B6 deficiency in MVM non-users was common and increased with age.


Assuntos
Deficiência de Vitaminas/epidemiologia , Suplementos Nutricionais/estatística & dados numéricos , Micronutrientes/administração & dosagem , Idoso , Biomarcadores/sangue , Fenômenos Fisiológicos da Nutrição do Idoso , Feminino , Humanos , Masculino , Micronutrientes/deficiência , Pessoa de Meia-Idade , Inquéritos Nutricionais , Necessidades Nutricionais , Estado Nutricional , Prevalência , Oligoelementos/administração & dosagem , Estados Unidos/epidemiologia , Vitaminas/administração & dosagem
20.
Clin Ther ; 40(4): 640-657, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29573851

RESUMO

PURPOSE: Evidence supporting the use of dietary supplements, in particular, multivitamin/multimineral supplements (MVMS), has been mixed, complicating the ability of health care professionals to recommend their use. To clarify the role that MVMS can play in supporting human health, a series of consensus statements was developed based on expert opinion. METHODS: A panel of 14 international experts in nutritional science and health care was convened to develop consensus statements related to using MVMS in supporting optimal human health. The modified Delphi process included 2 rounds of remote voting and a final round of voting at a roundtable meeting where evidence summaries were presented and discussed. The level of agreement with each of 9 statements was rated on a 5-point Likert scale: agree strongly; agree with reservation; undecided; disagree; or disagree strongly. Consensus was predefined as ≥80% of the panel agreeing strongly or agreeing with reservation to a given statement. FINDINGS: Consensus was reached for all statements. The panel determined that MVMS can broadly improve micronutrient intakes when they contain at least the micronutrients that are consumed insufficiently or have limited bioavailability within a specified population. MVMS formulations may also be individualized according to age, sex, life cycle, and/or other selected characteristics. There are specific biological processes and health outcomes associated with deficient, inadequate, and adequate micronutrient levels. Adequate intake is necessary for normal biological functioning required for good health; in some instances, higher than recommended micronutrient intakes have the potential to provide additional health benefits. Meeting daily intakes established by dietary reference values should be an explicit public health goal for individuals and populations. Use of MVMS is one approach to ensure that adequate micronutrient needs are met in support of biological functions necessary to maintain health. Long-term use of MVMS not exceeding the upper limit of recommended intakes has been determined to be safe in healthy adults. There is insufficient evidence to indicate that MVMS are effective for the primary prevention of chronic medical conditions, including cardiovascular disease and cancer. However, for certain otherwise healthy subpopulations (eg, pregnant women, older adults) and some individuals with existing medical conditions who experience inadequacies in micronutrient intake, addressing inadequacies by using MVMS can provide health benefits. IMPLICATIONS: This consensus panel has described key issues related to the use of MVMS among individuals at risk of or presenting with inadequacies in micronutrient intake or biomarker status.


Assuntos
Suplementos Nutricionais , Estado Nutricional , Vitaminas/administração & dosagem , Idoso , Disponibilidade Biológica , Doença Crônica , Consenso , Dieta , Feminino , Humanos , Masculino , Gravidez
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